This invention relates generally to strip type bus bars for use with terminal posts mounted on substrates such as printed circuit boards, and more particularly it relates to solder coated strip bus bars which can be mounted on a plurality of tereminal posts extending from some substrate, such as a printed circuit board, and substantiallly simultaneously soldered to selected ones of said terminal posts.
In the current state of the electronic art, it is quite common to utilize terminal posts which extend through a printed circuit board. Often it is desirable to provide bus bars which fit over the terminal posts. In many cases it is desirable that the bus bar fit over certain selected ones of the terminal posts in a line of terminal posts, and to electrically by-pass other certain terminal posts in said line of terminal posts.
The types of bus bars used in the foregoing application can be divided generally into two categories. In the first category are strip bus bars which are formed of a spring-like metallic material and which are cold worked to form a plurality of individual, clip-like elements which, when pressed over the bus bar, exert a continuous force against the terminal posts due to the spring-like nature of the material, and thereby maintain electrical contact with the terminal posts. In order to maintain this continuous force against the terminal posts, the aforementioned type bus bar must usually be formed into a rather elaborate configuration having a number of fingers or wings. Further, the stiff, spring-like material is fairly expensive and relatively difficult to form. Still further, because of the stiffness of the material required, there is very little room for mismatch of spacing between the post gripping portions of the bus bar and the post-like terminals over which it fits. Therefore, alignment problems occur with more frequency than is desirable and are difficult to correct.
The other general form of bus bar involves a strip of metal which has holes or semi-holes of two sizes formed therein along the length thereof. These two sizes consist of large holes and small holes. The large holes are made sufficiently large to fit around the terminal posts without making any physical contact therewith, thereby maintaining electrical isolation from the posts. The smaller holes fit around selected terminal posts and are intended to ultimately make electrical contact therewith. Discrete, doughnut-shaped rings of solder are dropped over those terminal posts which are to be soldered to the bus bar; those terminal posts being the posts which extend through the smaller holes. The entire assembly is then heated and the solder rings melt to form a permanent electrical connection between the bus bar and the selected terminal posts. The terminal posts which pass through the larger holes remain electrically isolated from the bus bar.
One disadvantage of the last-mentioned type of bus bar is the expense of selectively dropping a ring of solder around each terminal post which is to be secured to the bus bar. Futhermore it is possible that a given terminal post is so perfectly aligned with the small hole in the bus bar that no physical contact at any point exists between the terminal post and the bus bar. Then, when the solder ring dropped over the terminal post is melted, it is possible that no connection will be made between the terminal post and the bus bar, or at best, only a partial connection will be made. In other words, none or insufficient solder will flow between the post and the bus bar to make a solid, permanent connection therebetween.